Disorders and borders: Psychiatric genetics and nosology
Article first published online: 17 OCT 2013
Copyright © 2013 Wiley Periodicals, Inc.
American Journal of Medical Genetics Part B: Neuropsychiatric Genetics
Special Issue: Identifying the Origins of Mental Illness: A Festschrift in Honor of Ming T. Tsuang
Volume 162, Issue 7, pages 559–578, October 2013
How to Cite
2013. Disorders and Borders: Psychiatric Genetics and Nosology. Am J Med Genet Part B 162B:559–578..
- Issue published online: 17 OCT 2013
- Article first published online: 17 OCT 2013
- Manuscript Accepted: 7 MAY 2013
- Manuscript Received: 11 APR 2013
Over the past century, the definition and classification of psychiatric disorders has evolved through a combination of historical trends, clinical observations, and empirical research. The current nosology, instantiated in the DSM-5 and ICD-10, rests on descriptive criteria agreed upon by a consensus of experts. While the development of explicit criteria has enhanced the reliability of diagnosis, the validity of the current diagnostic categories has been the subject of debate and controversy. Genetic studies have long been regarded as a key resource for validating the boundaries among diagnostic categories. Genetic epidemiologic studies have documented the familiality and heritability of clinically defined psychiatric disorders and molecular genetic studies have begun to identify specific susceptibility variants. At the same time, there is growing evidence from family, twin and genomic studies that genetic influences on psychiatric disorders transcend clinical boundaries. Here I review this evidence for cross-disorder genetic effects and discuss the implications of these findings for psychiatric nosology. Psychiatric genetic research can inform a bottom-up reappraisal of psychopathology that may help the field move beyond a purely descriptive classification and toward an etiology-based nosology. © 2013 Wiley Periodicals, Inc.